ENI and both managers, neither of who has been charged, have denied any wrongdoing.
Production from the deepwater oil field is expected to begin in 2016 with the field estimated to hold up to 9.23 billion barrels of crude, equivalent to nearly a quarter of the country’s total proven reserves, according to industry figures.
“We are investigating many money transfers to many people in various countries who received sums that vary from millions of dollars to thousands of dollars,” the prosecutors said in the follow-up letter, seen by Reuters.
After the death of Abacha, a new Nigerian government annulled the deal. Malabu’s licence was reinstated in 2006.